This post reminds me of when I was playing around on this timelapse website before.
Want to see the effects of sedimentation over 30 years look no further then Lake Athabasca. It is insane how much things have changed up there over this time period and it is only a matter of a few more decades until Fort Chipewyan isn't waterfront property anymore.
https://earthengine.google.com/timel...,latLng&t=0.36
The biologists know and understand that our lakes and rivers are naturally dying from sedimentation and eutrophication. The only way these rivers will ever hold as many fish as they did in decades/centuries past is if steps are taken to not only combat mankinds effects but also to offset natural degradation of these rivers.
Simply put it is too easy to just blame mankind for our declining fish populations but many of these rivers have seen very significant change and damage from natural events(such as the Clearwater flooding in 2013 just to name one very relevant event related to this NCNT program). These events although natural can still have significant and negative effects on fish populations and if steps are not taken to recover these water bodies after such events then one has to expect changes to fish populations.
I could be wrong but I believe fisheries has largely gotten away from trying to fix/improve habitat like this. There are numerous old reports that talk about how back in the 60's etc they used to go out and try to create and improve spawning areas, removing natural fish barricades etc but I haven't read about much work like this being done in recent years(except for trying to fix some of the man made issues such as hanging culverts etc).
This is something they will have to start doing more of again if they expect these water bodies to thrive.